/*
 * Copyright (c) 2007-2012, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
/*
 * Copyright 1999-2002,2004 The Apache Software Foundation.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

// Sep 14, 2000:
//  Fixed serializer to report IO exception directly, instead at
//  the end of document processing.
//  Reported by Patrick Higgins <phiggins@transzap.com>

package com.sun.org.apache.xml.internal.serialize;

import java.io.IOException;

import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.xml.sax.AttributeList;
import org.xml.sax.Attributes;
import org.xml.sax.SAXException;

/**
 * Implements a text serializer supporting both DOM and SAX
 * serializing. For usage instructions see {@link Serializer}.
 * <p>
 * If an output stream is used, the encoding is taken from the
 * output format (defaults to <tt>UTF-8</tt>). If a writer is
 * used, make sure the writer uses the same encoding (if applies)
 * as specified in the output format.
 * <p>
 * The serializer supports both DOM and SAX. DOM serializing is done
 * by calling {@link #serialize} and SAX serializing is done by firing
 * SAX events and using the serializer as a document handler.
 * <p>
 * If an I/O exception occurs while serializing, the serializer
 * will not throw an exception directly, but only throw it
 * at the end of serializing (either DOM or SAX's {@link
 * org.xml.sax.DocumentHandler#endDocument}.
 *
 *
 * @author <a href="mailto:arkin@intalio.com">Assaf Arkin</a>
 * @see Serializer
 */
public class TextSerializer extends BaseMarkupSerializer {

    /**
     * Constructs a new serializer. The serializer cannot be used without
     * calling {@link #setOutputCharStream} or {@link #setOutputByteStream}
     * first.
     */
    public TextSerializer() {
        super(new OutputFormat(Method.TEXT, null, false));
    }

    public void setOutputFormat(OutputFormat format) {
        super.setOutputFormat(format != null ? format : new OutputFormat(Method.TEXT, null, false));
    }

    //-----------------------------------------//
    // SAX content handler serializing methods //
    //-----------------------------------------//

    public void startElement(String namespaceURI, String localName, String rawName, Attributes attrs) throws SAXException {
        startElement(rawName == null ? localName : rawName, null);
    }

    public void endElement(String namespaceURI, String localName, String rawName) throws SAXException {
        endElement(rawName == null ? localName : rawName);
    }

    //------------------------------------------//
    // SAX document handler serializing methods //
    //------------------------------000---------//

    public void startElement(String tagName, AttributeList attrs) throws SAXException {
        boolean preserveSpace;
        ElementState state;

        try {
            state = getElementState();
            if (isDocumentState()) {
                // If this is the root element handle it differently.
                // If the first root element in the document, serialize
                // the document's DOCTYPE. Space preserving defaults
                // to that of the output format.
                if (!_started)
                    startDocument(tagName);
            }
            // For any other element, if first in parent, then
            // use the parnet's space preserving.
            preserveSpace = state.preserveSpace;

            // Do not change the current element state yet.
            // This only happens in endElement().

            // Ignore all other attributes of the element, only printing
            // its contents.

            // Now it's time to enter a new element state
            // with the tag name and space preserving.
            // We still do not change the curent element state.
            state = enterElementState(null, null, tagName, preserveSpace);
        } catch (IOException except) {
            throw new SAXException(except);
        }
    }

    public void endElement(String tagName) throws SAXException {
        try {
            endElementIO(tagName);
        } catch (IOException except) {
            throw new SAXException(except);
        }
    }

    public void endElementIO(String tagName) throws IOException {
        ElementState state;

        // Works much like content() with additions for closing
        // an element. Note the different checks for the closed
        // element's state and the parent element's state.
        state = getElementState();
        // Leave the element state and update that of the parent
        // (if we're not root) to not empty and after element.
        state = leaveElementState();
        state.afterElement = true;
        state.empty = false;
        if (isDocumentState())
            _printer.flush();
    }

    public void processingInstructionIO(String target, String code) throws IOException {
    }

    public void comment(String text) {
    }

    public void comment(char[] chars, int start, int length) {
    }

    public void characters(char[] chars, int start, int length) throws SAXException {
        ElementState state;

        try {
            state = content();
            state.doCData = state.inCData = false;
            printText(chars, start, length, true, true);
        } catch (IOException except) {
            throw new SAXException(except);
        }
    }

    protected void characters(String text, boolean unescaped) throws IOException {
        ElementState state;

        state = content();
        state.doCData = state.inCData = false;
        printText(text, true, true);
    }

    //------------------------------------------//
    // Generic node serializing methods methods //
    //------------------------------------------//

    /**
     * Called to serialize the document's DOCTYPE by the root element.
     * <p>
     * This method will check if it has not been called before ({@link #_started}),
     * will serialize the document type declaration, and will serialize all
     * pre-root comments and PIs that were accumulated in the document
     * (see {@link #serializePreRoot}). Pre-root will be serialized even if
     * this is not the first root element of the document.
     */
    protected void startDocument(String rootTagName) throws IOException {
        // Required to stop processing the DTD, even though the DTD
        // is not printed.
        _printer.leaveDTD();

        _started = true;
        // Always serialize these, even if not te first root element.
        serializePreRoot();
    }

    /**
     * Called to serialize a DOM element. Equivalent to calling {@link
     * #startElement}, {@link #endElement} and serializing everything
     * inbetween, but better optimized.
     */
    protected void serializeElement(Element elem) throws IOException {
        Node child;
        ElementState state;
        boolean preserveSpace;
        String tagName;

        tagName = elem.getTagName();
        state = getElementState();
        if (isDocumentState()) {
            // If this is the root element handle it differently.
            // If the first root element in the document, serialize
            // the document's DOCTYPE. Space preserving defaults
            // to that of the output format.
            if (!_started)
                startDocument(tagName);
        }
        // For any other element, if first in parent, then
        // use the parnet's space preserving.
        preserveSpace = state.preserveSpace;

        // Do not change the current element state yet.
        // This only happens in endElement().

        // Ignore all other attributes of the element, only printing
        // its contents.

        // If element has children, then serialize them, otherwise
        // serialize en empty tag.
        if (elem.hasChildNodes()) {
            // Enter an element state, and serialize the children
            // one by one. Finally, end the element.
            state = enterElementState(null, null, tagName, preserveSpace);
            child = elem.getFirstChild();
            while (child != null) {
                serializeNode(child);
                child = child.getNextSibling();
            }
            endElementIO(tagName);
        } else {
            if (!isDocumentState()) {
                // After element but parent element is no longer empty.
                state.afterElement = true;
                state.empty = false;
            }
        }
    }

    /**
     * Serialize the DOM node. This method is unique to the Text serializer.
     *
     * @param node The node to serialize
     */
    protected void serializeNode(Node node) throws IOException {
        // Based on the node type call the suitable SAX handler.
        // Only comments entities and documents which are not
        // handled by SAX are serialized directly.
        switch (node.getNodeType()) {
            case Node.TEXT_NODE: {
                String text;

                text = node.getNodeValue();
                if (text != null)
                    characters(node.getNodeValue(), true);
                break;
            }

            case Node.CDATA_SECTION_NODE: {
                String text;

                text = node.getNodeValue();
                if (text != null)
                    characters(node.getNodeValue(), true);
                break;
            }

            case Node.COMMENT_NODE:
                break;

            case Node.ENTITY_REFERENCE_NODE:
                // Ignore.
                break;

            case Node.PROCESSING_INSTRUCTION_NODE:
                break;

            case Node.ELEMENT_NODE:
                serializeElement((Element) node);
                break;

            case Node.DOCUMENT_NODE:
                // !!! Fall through
            case Node.DOCUMENT_FRAGMENT_NODE: {
                Node child;

                // By definition this will happen if the node is a document,
                // document fragment, etc. Just serialize its contents. It will
                // work well for other nodes that we do not know how to serialize.
                child = node.getFirstChild();
                while (child != null) {
                    serializeNode(child);
                    child = child.getNextSibling();
                }
                break;
            }

            default:
                break;
        }
    }

    protected ElementState content() {
        ElementState state;

        state = getElementState();
        if (!isDocumentState()) {
            // If this is the first content in the element,
            // change the state to not-empty.
            if (state.empty)
                state.empty = false;
            // Except for one content type, all of them
            // are not last element. That one content
            // type will take care of itself.
            state.afterElement = false;
        }
        return state;
    }

    protected String getEntityRef(int ch) {
        return null;
    }

}
